The ATH-WS770iS Solid Bass over-ear headphones combine exclusive 53 mm Deep Motion Drivers with a rigid housing structure and Triple Venting System to provide clear, full-range audio reproduction with invigorating bass. The large diaphragm surface area of the drivers causes considerable air movement, which makes the rich, high-fidelity bass sound possible. The top-mounted PCB equalizes the air pressure behind the diaphragm, thus balancing the sound and keeping distortion to a minimum. Rigid housings, comprised of an aluminum centerpiece and an aluminum stabilizer ring, dispel any vibration, while three ideally placed vents effectively dampen the airflow within each housing. The result is deep, beautifully textured bass along with crystal-clear reproduction in the mid-to-high frequencies.